Emmy Rossum

Happy Now (2001) [Nicky Trent/Jenny Thomas]: Playing a dual role, “Jenny” is accidentally killed by two men (I don’t know the circumstances or the killers’ identities). I assume that “Nicky” survives the movie. (Thanks to Ben and Victor)

The Phantom of the Opera (2004) [Christine Daaé]: Reportedly dies (off-screen), presumably of old age/natural causes, in the time between the main portion of the film and an epilogue; and elderly Patrick Wilson is shown visiting her grave at the end of the movie. (Thanks of JF)